Articles of apparel including auxetic materials

Abstract

An article of apparel includes a base layer and an auxetic layer. The base layer includes a four way stretch material. The auxetic layer is coupled to the base layer and includes an auxetic structure defining a repeating pattern of voids. In accordance with one exemplary embodiment of the disclosure, each void has a reentrant shape and is at least partially filled with a foam or a hot melt material.

What is claimed is: 
     
       1. An article of apparel comprising:
 a base layer comprising a four way stretch material; and 
 an auxetic layer coupled to the base layer, the auxetic layer comprising an auxetic structure including a plurality of interconnected members defining a repeating pattern of voids, wherein each void has a reentrant shape, and wherein the base layer is exposed by at least one void of the auxetic layer. 
 
     
     
       2. The article of apparel of  claim 1  wherein the auxetic structure is comprised of a polymer material. 
     
     
       3. The article of apparel of  claim 2  wherein the polymer material is a foam material. 
     
     
       4. The article of apparel of  claim 1  further comprising a foam layer between the base layer and the auxetic layer. 
     
     
       5. The article of apparel of  claim 1  wherein the base layer is positioned on a first side of the auxetic layer, the article of apparel further comprising a cover layer positioned on a second side of the auxetic layer. 
     
     
       6. The article of apparel of  claim 5  wherein the base layer is connected to the cover layer in a plurality of the voids. 
     
     
       7. The article of apparel of  claim 1  wherein each void has a bow-tie shape. 
     
     
       8. The article of apparel of  claim 1  wherein the interconnected members are between 1 mm and 5 mm wide. 
     
     
       9. The article of apparel of  claim 1 , wherein the article of apparel is a garment. 
     
     
       10. The article of apparel of  claim 1 , wherein the article of apparel is a shoe upper. 
     
     
       11. The article of apparel of  claim 1 , wherein the article of apparel is a hat. 
     
     
       12. The article of apparel of  claim 1 , wherein the article of apparel is a protective pad. 
     
     
       13. The article of apparel of  claim 1 , wherein the article of apparel is a strap for a bag. 
     
     
       14. An article of apparel comprising:
 a four way stretch material; and 
 an auxetic structure coupled to the four way stretch material, the auxetic structure including a plurality of interconnected members forming an array of reentrant polygonal shapes positioned on the article of apparel. 
 
     
     
       15. An article of apparel comprising:
 a first layer comprising an elastic sheet; and 
 a second layer coupled to the first layer, the second layer comprising a structure including a plurality of interconnected members forming a uniform array of polygonal shapes defining voids in the second layer, each of the interconnected members directly coupled to the first layer, the structure having a Poisson's ratio of substantially zero or less than zero. 
 
     
     
       16. The article of apparel of  claim 15  wherein the first layer is exposed through the voids in the second layer. 
     
     
       17. The article of apparel of  claim 14  wherein each of the interconnected members is directly coupled to the four way stretch material, and wherein the four way stretch material is visible through the auxetic structure between the interconnected members. 
     
     
       18. The article of apparel of  claim 1  wherein the base layer is exposed through each void in the repeating pattern of voids. 
     
     
       19. The article of apparel of  claim 1  wherein the auxetic layer is a printed layer. 
     
     
       20. The article of apparel of  claim 1 , wherein the voids are planar. 
     
     
       21. The article of apparel of  claim 20 , wherein the voids are polygonal. 
     
     
       22. The article of apparel of  claim 1 , wherein the voids are substantially uniform in size and shape.